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Beyond Superdome

Which brings us around the HP Tukwila Integrity family photo to the Superdome 2, about which HP will say very little today because it is not shipping until the second half of 2010, along with the BladeSystem Matrix machine running HP-UX and offering a ready-to-go virtualized, cloudy infrastructure stack.

The many prior generations of Superdome machines were based on homegrown chipsets. The original "Yosemite" chipset for the Superdomes used PA-RISC 8600 processors - Yosemite Park being where Half Dome mountain is located and where Dick Lampman, director of HP Labs when the original Superdomes were created a decade ago, used to climb. The kickers were the "Pinnacles" sx1000, finally supporting Itanium, and the "Arches" sx2000, supporting the Itanium 2 processors. With the Superdome 2, HP continues in this tradition with the sx3000 chipset, which I am told did not have a code name but I simply do not believe it. That's about where the similarity ends.

With Superdome 2, HP is making some big changes. First, HP is ditching the four-socket cell board architecture and non-standard, fatter system rack that has defined the PA-RISC and Integrity Superdomes from here on out. The Superdome 2 is based on a modified c7000 enclosure, which is 10U high and has room for eight full-height server blades. But you can't cram all that SMP/NUMA goodness of the Superdome into a blade that is only 10U high and you can't just cobble together a Blade Link on the front of the blades to lash all eight blades in a chassis into a single system image.

And so, HP cut the top off the c7000 chassis and added another 8U of space for all the Superdome 2 and sx3000 goodies. Now, instead of cramming 64 cores into a rack that is fatter than everything else in the server room, HP can put 64-cores in under a half rack of space. Some shops are going to need 128-core images too, like they have with existing Integrity Superdomes based on the 9000 and 9100 series of dual-core Itanium 2 chips, and some are really probably wondering where the heck are the 256-core machines.

Each 18U-high Tukwila blade has 32 DDR3 DIMM sockets and two processor sockets, for a maximum of eight cores. If you assume 8 GB memory, that's 2 TB of main memory for 64 cores, which is a perfectly respectable amount of memory that will no doubt double to 4 TB when 16 GB memory sticks are available. (Probably by the time Superdome 2 ships, in fact).

Bresniker said that the sx3000 chip had three elements, including the I/O chip, node controller interfaces, and a crossbar chip. But oddly enough, all the BladeSystem I/O at the bottom of the blade is also available to the Superdome 2 nodes, so they can use Virtual Connect and integrated switching if customers want to go that way.

With Superdome 2, the crossbar fabric is fully redundant and fully fault tolerant, unlike the prior Superdome crossbar, and everything in the system is dual-path and can automatically fail over and retry in the event a component fails. This dual fabric is active/active, and the system load balances across both sets of paths between system components until something fails. When you identity and fix a broken component, which is possible because the system has hot-swap CPU, memory, and I/O, the crossbar figures out when it is fixed and rebalances the load.

Superdome 2 will also support PCI-Express 2.0 peripherals, and I/O can be added to the system independently of CPU and memory boards. So now you don't have to buy a cell board just because you want more I/O. Even though it is hard to believe, there are some I/O intensive workloads where customers have topped out the I/O slots in a Superdome. Exactly how this works is unclear, but as soon as El Reg gets the details, we'll let you know.

The upshot of the blading of the Superdome line is that an entry Superdome 2 box will cost around 40 per cent less than an Superdome box. Precise pricing was not announced, since the machines are not yet shipping.

When I asked if it was possible to plunk a pair of Xeon 7500 processors in a modified Superdome 2 motherboard and use the sx3000 chipset to make a very big Xeon machine, Bresniker and Bartlett just laughed. And they had to jump to the next call, so I didn't get a chance to ask about the possibilities of HP-UX being put on such a machine. But it is something to think about. ®